Digital cameras and optical imaging devices employ image sensors. Image sensors convert optical images to digital data that may be displayed as digital images. An image sensor includes an array of photosensors, which are unit devices for the conversion of an optical image into digital data. Photosensors often manifest as charge-coupled devices (CCDs) or complementary metal oxide semiconductor (CMOS) devices. However, CMOS photosensors have recently received more attention. Relative to CCD photosensors, CMOS photosensors provide lower power consumption, smaller size, and faster data processing. Further, CMOS photosensors provide a direct digital output of data, and generally have a lower manufacturing cost compared with CCD photosensors.